IntelFsp2WrapperPkg/Library/SecFspWrapperPlatformSecLibSample/SecPlatformInformation.c

   1 /** @file
   2   Sample to provide SecPlatformInformation function.
   3
   4   Copyright (c) 2014, Intel Corporation. All rights reserved.<BR>
   5   SPDX-License-Identifier: BSD-2-Clause-Patent
   6
   7 **/
   8
   9 #include <PiPei.h>
  10
  11 #include <Ppi/SecPlatformInformation.h>
  12 #include <Ppi/TopOfTemporaryRam.h>
  13
  14 #include <Library/BaseMemoryLib.h>
  15 #include <Library/DebugLib.h>
  16
  17 /**
  18   This interface conveys state information out of the Security (SEC) phase into PEI.
  19
  20   @param[in]     PeiServices               Pointer to the PEI Services Table.
  21   @param[in,out] StructureSize             Pointer to the variable describing size of the input buffer.
  22   @param[out]    PlatformInformationRecord Pointer to the EFI_SEC_PLATFORM_INFORMATION_RECORD.
  23
  24   @retval EFI_SUCCESS           The data was successfully returned.
  25   @retval EFI_BUFFER_TOO_SMALL  The buffer was too small.
  26
  27 **/
  28 EFI_STATUS
  29 EFIAPI
  30 SecPlatformInformation (
  31   IN CONST EFI_PEI_SERVICES                     **PeiServices,
  32   IN OUT   UINT64                               *StructureSize,
  33      OUT   EFI_SEC_PLATFORM_INFORMATION_RECORD  *PlatformInformationRecord
  34   )
  35 {
  36   UINT32      *Bist;
  37   UINT32      Size;
  38   UINT32      Count;
  39   UINT32      TopOfTemporaryRam;
  40   VOID        *TopOfTemporaryRamPpi;
  41   EFI_STATUS  Status;
  42
  43   DEBUG ((DEBUG_INFO, "SecPlatformInformation\n"));
  44
  45   Status = (*PeiServices)->LocatePpi (
  46                              PeiServices,
  47                              &gTopOfTemporaryRamPpiGuid,
  48                              0,
  49                              NULL,
  50                              (VOID **) &TopOfTemporaryRamPpi
  51                              );
  52   if (EFI_ERROR (Status)) {
  53     return EFI_NOT_FOUND;
  54   }
  55
  56   //
  57   // The entries of BIST information, together with the number of them,
  58   // reside in the bottom of stack, left untouched by normal stack operation.
  59   // This routine copies the BIST information to the buffer pointed by
  60   // PlatformInformationRecord for output.
  61   //
  62   TopOfTemporaryRam = (UINT32)(UINTN)TopOfTemporaryRamPpi - sizeof (UINT32);
  63   TopOfTemporaryRam -= sizeof(UINT32) * 2;
  64   Count             = *((UINT32 *)(UINTN) (TopOfTemporaryRam - sizeof (UINT32)));
  65   Size              = Count * sizeof (IA32_HANDOFF_STATUS);
  66
  67   if ((*StructureSize) < (UINT64) Size) {
  68     *StructureSize = Size;
  69     return EFI_BUFFER_TOO_SMALL;
  70   }
  71
  72   *StructureSize  = Size;
  73   Bist            = (UINT32 *) (TopOfTemporaryRam - sizeof (UINT32) - Size);
  74
  75   CopyMem (PlatformInformationRecord, Bist, Size);
  76
  77   return EFI_SUCCESS;
  78 }